A short summary on what this stuff is:
The Guidance Automation Toolkit is an extension to Visual Studio 2005 which allows architects to author rich, integrated user experiences for reusable assets including frameworks, components and patterns. The resulting Guidance Packages composed of templates, wizards and recipes help developers build solutions in a way consistent with the architecture guidance. The Guidance Automation Extensions for Visual Studio 2005 is a runtime component that must be installed to use the Guidance Automation Toolkit itself, as well as to use any guidance packages built using the Guidance Automation Toolkit. For more information, see Introduction to the Guidance Automation Toolkit.And note XInclude amongst new features:
New in this release
The December 2005 CTP of the Guidance Automation Toolkit and Guidance Automation Extensions is a minor update to the previous May 2005 CTP. In addition to being updated to work on the final release of Visual Studio 2005, a number of new features have been added. These include:
o Integration with the T4 Text Templating Engine (which is also used by the DSL Toolkit)
o T4 Templates can now be associated with Item Templates
o Recipe references can now be placed on cascading menus
o Two new extensibility points have been added: the Action Execution Service and the Action Coordination Service
o XInclude can be used in recipe definition files to reference XML fragments stored in external files